<template>
  <el-container class="home-container">
    <el-header><!-- 头部区 -->
      <div>
        <img src="../assets/logo2.png" alt="" height="50px" />
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!-- 页面主体区域 -->
    <el-container>
      <!-- 侧边栏 -->
      <el-aside :width="isCollapse ? '64px' : '200px'">
          <!-- 折叠条 -->
          <div class="toggle-button" @click="toggleCollapse()">|||</div>
          <!-- 侧边栏菜单区域 -->
          <el-menu background-color="#333744" text-color="#fff" 
          active-text-color="#409BFF" :unique-opened="true" 
          :collapse="isCollapse" :collapse-transition="false"
          :router="true" :default-active="activePath">
              <!-- 一级菜单 -->
              <el-submenu :index="item.id+''" v-for="item in menuList" :key="item.id">
                  <!-- 一级菜单的模板区域 -->
                  <template slot="title">
                      <!-- 图标 -->
                      <i :class="iconsObj[item.id]"></i>
                      <!-- 菜单名称 -->
                      <span>{{item.authName}}</span>
                  </template>
                  <!-- 二级菜单 -->
                  <el-menu-item :index="'/'+subItem.path" v-for="subItem in item.children" 
                      :key="subItem.id" @click="saveNavState('/'+subItem.path)">
                      <template slot="title">
                          <i class="el-icon-menu"></i>
                          <span slot="title">{{subItem.authName}}</span>
                      </template>
                  </el-menu-item>
              </el-submenu>
          </el-menu>
      </el-aside>
      <!-- 右侧内容主体 -->
      <el-main>
        <!-- 路由占位符 -->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>
 
<script>
export default {
  data(){
    return {
      //左侧菜单数据
      menuList:[],
      iconsObj: {
        '125':'el-icon-user-solid',//用户管理
        '103':'el-icon-s-check',//权限管理
        '101':'el-icon-s-goods',//商品管理
        '102':'el-icon-s-order',//订单管理
        '145':'el-icon-s-data',//数据管理
      },
      isCollapse: false,
      activePath: '' //被激活的菜单
    }
  },
  created(){
    this.getMenuList();
    this.activePath = window.sessionStorage.getItem('activePath');
  },
  methods: {
    logout() {
      window.sessionStorage.clear();
      this.$router.push("/login");
    },
    //获取所有的菜单
    async getMenuList(){
      const {data:res} = await this.$http.get('menus');
      if(res.meta.status !== 200) return this.$message.error(res.meta.msg);
      this.menuList = res.data;
      console.log(res);
    },
    //点击按钮，切换菜单的折叠与展开
    toggleCollapse(){
      this.isCollapse = !this.isCollapse;
    },
    //保存菜单的index值（保持菜单的激活状态）
    saveNavState(activePath){
      window.sessionStorage.setItem('activePath',activePath);
      this.activePath = activePath;
    }
  },
};
</script>
 
<style lang="less" scoped>
.home-container {
  height: 100%;
}
.el-header {
  background-color: #373d41;
  display: flex; //设置显示为flex布局
  justify-content: space-between; //设置为flex左右布局
  padding-left: 0; //左内边距为0（Logo贴左边）
  align-items: center; //元素上下居中（防止右边按钮贴上下边）
  color: #fff;
  font-size: 20px;
  > div {
    //内嵌的div样式
    display: flex;
    align-items: center; //Logo和文字上下居中
    span {
      margin-left: 15px; //文字左侧设置间距，防止与Logo紧贴
    }
  }
}
.el-aside {
  background-color: #333744;
  .el-menu{
    border-right: none;
  }
}
.el-main {
  background-color: #eaedf1;
}
.toggle-button{
  background-color: #4A5064;//背景色(浅灰)
  font-size: 10px;//字体大小10像素
  line-height: 24px;//行高24像素
  color: #fff;//字体颜色白色
  text-align: center;//字体居中
  letter-spacing: 0.2em;//字体之间的距离
  cursor: pointer;//鼠标的形状（手形）
}
</style>